Turbochargers are used in a variety of vehicle and stationary applications powered by gasoline and diesel internal combustion engines. The turbochargers that are used in each different dynamic or actual application are subjected to different turbocharger operating conditions, e.g., different operating speeds, temperatures, and duration. Additionally, turbochargers that are made for and used with a particular application, e.g., diesel-powered vehicles, may also be exposed to different turbocharger operating conditions depending on how the particular application is operated. Accordingly, turbochargers designed for use in a particular application such as a diesel-powered truck, can be subjected to a wide range operating conditions such as temperature, speed, and duration of use that will impact the service life of the turbocharger.
In an effort to reduce or minimize the probability of a turbocharger-related failure adversely impacting the operational efficiency of the particular application, it is desired that the turbocharger be removed for servicing or replacement prior to failing in service. Devices and methods known in the art for indicating such turbocharger service intervals include those that are designed to measure turbocharger service duration, i.e., hours or vehicle mileage. Such known devices provide an indication of whether turbocharger service is needed based on a preset duration. A disadvantage of such turbocharger service monitor devices is that they are designed to predict the turbocharger service interval for a particular turbocharger independent of the actual operating or performance conditions of that turbocharger. Additionally, the preset duration used to predict such service interval is intentionally selected to be conservative to minimize the possibility of in-service turbocharger failure. Thus, such known turbocharger service monitor devices can cause some turbochargers to be replaced or repaired before any such repair is actually required, are subjected to relatively mild operating conditions, and can cause some turbochargers to fail in service, if subjected to relatively extreme operating conditions. Underestimating the actual service life of a turbocharger is not desired because premature replacement of the turbochargers incurs both unnecessary expense and requires that the turbocharged application be prematurely removed from service. Overestimating the actual service life of a turbocharger is also not desired for the obvious reason of causing an in-service turbocharger failure, which both unpredictably removes the turbocharged application from service and could cause damage to other engine systems.
It is, therefore, desired that a turbocharger monitoring device/method be constructed that is capable of providing an indication of recommended or needed turbocharger based on the actual turbocharger operating conditions, thereby extending the service interval for turbochargers subjected to mild operating conditions and reducing the service interval for turbochargers subjected to extreme operating conditions to optimize turbocharger use.